スポット溶接構造の公称構造応力算出法（円筒殻構造への適用）

摘要

In order to improve a fatigue life prediction technology of a spot welded structure, the method to evaluate the fatigue life by a nominal structural stress (NSS) was proposed. The authors have proposed the method to obtain the NSS accurately for spot welded structure composed of flat sheets. The proposed method uses the general loads of the nugget and the displacements on the circumference of the diameter D with the center of the nugget, which are obtained from finite element analysis. In this study, the proposed method was applied to a spot welded cylindrical shell structure. As the result, it was found that the proposed method was able to accurately obtain the NSS by using the displacements on the circumference of the small diameter D.%CAEによるスポット溶接構造疲労寿命予測法rnの一つに，スポット溶接の局所的な応力集中を含まずrn構造的な応力集中を表す公称構造応力をパラメータとrnして予測する方法がある．この方法では評価対象rnのナゲット端に発生する最大主応力である公称構造応rn力を精度良く求めることが重要となる．